EFFORS will demonstrate the technical ability and economic viability of satellite based support services to improve the prediction of flash flooding in order to protect critical infrastructures. As pilot areas the Mürz valley (Austria) and the Berchtesgaden area (Germany) were chosen. EFFORS will provide relevant data about flood evolution on short time scales and it will be based on the combination of satellite data and ground-based measurements. The intention is to collect, combine and process heterogeneous data and to deliver the final information directly to the users. The technical concept foresees a network of sensors on the ground to measure key variables of the two pilot areas (e.g. water level, discharges, and precipitation). The collected data will be transmitted via either satellite or terrestrial communications networks to a processing center. In order to reduce the costs communication sensors will be activated using threshold values, i.e. stations are activated in a watershed only when measurements at a given station exceeds the defined threshold. EFFORS promotes user-driven introduction for an affordable, commercially viable real-time flood forecasting service by combining existing space and terrestrial technologies together in a flexible and modular integrated system.